Process for the preparation of the (+)-antipode of (E)-1-cyclohexyl-4,4-dimethyl-3-hydroxy-2-(1,2,4-triazol-1-yl)-pent-1-ene

Abstract

A process for the preparation of the (+)-antipode of (E)-1-cyclohexyl-4,4-dimethyl-3-hydroxy-2-(1,2,4-tri-azol-1-yl)-pent -1-ene of the formula ##STR1## which comprises reacting the (E)-isomer of 1-cyclohexyl-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-en-3-one of the formula ##STR2## with lithium aluminum hydride in the presence of an inert organic diluent and in the presence of a chiral amino alcohol at a temperature between -80° C. and +50° C. The (+)-antipode is produced in high selectivity, using (+)-N-methyl-ephedrine.

We claim: 
     
       1. A process for the preparation of the (+)-antipode of (E)-1-cyclohexyl-4,4-dimethyl-3-hydroxy-2-(1,2,4-triazol-1-yl)-pent-1-ene of the formula ##STR7## which comprises reacting the (E)-isomer of 1-cyclohexyl-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-en-3-one of the formula ##STR8## with lithium aluminum hydride in the presence of an inert organic diluent and in the presence of the (+)-antipode of N-methyl-ephedrine and in the presence of N-ethyl-aniline at a temperature between -80° C. and +50° C. 
     
     
       2. A process according to claim 1, wherein the inert organic diluent is diethyl ether, tetrahydrofuran or tert.-butyl methyl ether. 
     
     
       3. A process according to claim 1, wherein the reaction is carried out at a temperature between -70° C. and +40° C. 
     
     
       4. A process according to claim 1, wherein 1 to 5 mols of lithium aluminum hydride and 1 to 5 mols of the N-methyl-ephedrine are employed per mol of the (E)-isomer of 1-cyclo-hexyl-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-en-3-one. 
     
     
       5. A process according to claim 4, wherein during the reaction there are also present 2 to 10 mols of the N-ethyl-aniline.